The ASHRAE young engineers heard about the free cooling system in the recent tour of the DTE Vantage Dearborn Central Energy Plant. The free cooling …
Hydronic System Design – High Delta T Can Improve Boiler Efficiency (Part 2 of 4)
How can you increase the operating efficiency of your condensing boiler heating system? This question was raised in the last R. L. Deppmann Monday Morning …
Ice Rink Cooling System – Commissioning the Glycol Expansion Tank
A customer recently called us about an unusual occurrence in a closed hydronic cooling system for an ice rink. The system was filled using a …
Constant Speed 2-Way Control vs. Variable Speed Pumps for Heating and Cooling Coils (Part 2)
An engineer asked a question about using a variable speed pump for air temperature control in lieu of a two-way control valve. What are the …
Constant Speed 2-Way Control vs. Variable Speed Pumps for Heating and Cooling Coils (Part 1)
An engineer asked a question about using variable speed pumps for air temperature control in lieu of a two-way control valve. The question clearly makes you …
Hydronic Primary-Secondary Piping – How Important are the Two Close Tees?
Every year we get questions about the importance of primary-secondary piping rules around boilers and coils. Recently, I also received a call about using a …
Solving Minimum Flow in a Primary Variable System (Part 3)
The engineer is aware of the importance of minimum flow to the pumps in hydronic systems. The R. L. Deppmann Monday Morning Minutes Part 1 …
Minimum Flow in Variable Speed Pumps for Building Hydronic HVAC Systems (Part 2)
The HVAC engineer designing a hydronic system understands the need to protect the circulating pumps from a dead head or no flow condition. This week, …
Variable Speed Chilled Water Systems: Demand Reset
There are multiple methods to vary pump speed in HVAC chilled water systems. A common method is the use of a differential pressure transmitter at …
Cooling Tower Spring Startup Tips
The weather is warming, and our attention turns away from heating and toward system air conditioning. To protect the cooling tower pumps, we offer a …